An astronomical clock is known from EP-Patent application No. 107 177. A rather complicated and approximate drive for the moon's image is provided with this known clock, whereby the clock movement drives the moon's image through a geartrain so that it makes one daily revolution, continuously changing the moon's phase. The rising and setting of the moon are indicated through markings for the horizon. A presentation of the course of the sun or a differentiation of the moon by day or night is not provided for in this known clock.